I have a 88' bronco xlt. it is a 5.0 and I think it is the 4eod. It slip's bad in first gear then slams into second. It keeps trying to go to high gear or overdrive. The engine runs ruff. It has been sitting for two years and I think it is just bad gas and a gunked up fuel system. Do I need a new trans?? If so does any one have any help? Can I go to a c-4, c-6, aod?????

 

First step is to find out what tranny you have for sure. Does it have overdrive?

 

it should be the AOD.

 

i'd first do a major tune up. i thought my tranny was messing up one time when i bought a bronco until i changed the spark plugs and it helped out a lot.